The present invention relates, in general, to electronics, and more particularly, to methods of forming semiconductor devices and structure.
In the past, the semiconductor industry utilized various methods and structures to integrate capacitors onto a semiconductor die with other active and passive elements. For example, it often was desirable to use capacitors to integrate a filter onto a semiconductor die. Parallel plate capacitors often were used for such applications. However, parallel plate capacitors occupied a large area of a semiconductor die. Other methods of forming capacitors utilized P-N junctions such as a junction of a diode or a transient voltage suppression (TVS) device. However, the structures of these devices often occupied a large die area or else did not provide a large enough capacitance value.
Accordingly, it is desirable to have a semiconductor device that provides a large capacitance and that utilizes a small die area.
For simplicity and clarity of the illustration, elements in the figures are not necessarily to scale, and the same reference numbers in different figures denote the same elements. Additionally, descriptions and details of well-known steps and elements are omitted for simplicity of the description. As used herein current carrying electrode means an element of a device that carries current through the device such as a source or a drain of a MOS transistor or an emitter or a collector of a bipolar transistor or a cathode or anode of a diode, and a control electrode means an element of the device that controls current through the device such as a gate of a MOS transistor or a base of a bipolar transistor. Although the devices are explained herein as certain N-channel or P-Channel devices, a person of ordinary skill in the art will appreciate that complementary devices are also possible in accordance with the present invention. It will be appreciated by those skilled in the art that the words during, while, and when as used herein are not exact terms that mean an action takes place instantly upon an initiating action but that there may be some small but reasonable delay, such as a propagation delay, between the reaction that is initiated by the initial action. For clarity of the drawings, doped regions of device structures are illustrated as having generally straight line edges and precise angular corners. However, those skilled in the art understand that due to the diffusion and activation of dopants, the edges of doped regions generally may not be straight lines and the corners may not be precise angles.